Lifting jack



March 2, 1948. c. A. CRANE 2,437,078

` LIFTING JACK Y Filed April 17, 1946 2 sheets-sheet 1 Patented Mar. 2, 1948 UNITED STATES lPATENT OFFICE LIFTING JACK charles A. crane, chicago, 111.

Application April 17, 1946, Serial No. 662,815

(ci. 'x4-52s) 3 Claims.

1 The invention relates generally to lifting jacks and more particularly to a novel pawl carrier for a pawl and ratchet type jack or the like. The invention has among its objects the production of a pawl carrier which is stronger and more durable than prior devices and which may be constructed to provide any desired leverage.

Another object of the inventi-on is the production ot such a device which is relatively inexpensive. to manufacture and which may be used as a replacement in jacks of` this type now in use.

Many other objects and advantages of the construction herein shown and described will be obvious to those skilled in the art from the disclosure herein given.

VIn the drawings where like reference characters indicate like -orrcorresponding parts:

Fig. l is a side elevational view of a portion of .a ratchet type jack embodying the present invention;

Fig. 2 is a tcp plan view of a pawl carrier ernbodying the present invention;V

Fig. 3 isa side elevational view of one section of the carrier illustrated in Fig. 2;

Fig. 4 is an end elevational view of the carrier illustrated in Fig. 2; and

Fig. 5 is a sectional view taken approximately on the line 5-5 of Fig. 2.

Referring to Fig. 1, the present invention is illustrated in combination-with a ratchet type jack of the type presently lin use which comprises a housing designated generally by the numeral l of which only the upper portion is shown in the gure, the lower portion terminating in a suitable base.

Slidably mounted in the housing I is a toothed rack member 2, the latter being movable vertically in a suitable channel formed in the housing I, the upper end of the member 2 terminating in a suitable work engaging cap 3. The member 2 is heid in an extended position by a detent pawl llpivotally supported by the housing I, as indicated at 5, thepawl 4 having teeth 6 thereon engageable with similar teeth 'I on the member 2. Thus as the latter is extended upwardly, the detent pawl 4 will maintain the member 2 in its extended position.

Pivotally sup-ported in the housing I is a pawl carrier indicated generally bythe numeral 8, the latter having oppositely disposed trunnions 9 journaled in suitable bushings Il (only one of which is' shown in Fig. .1), The bushings II, in the present instance, are closed at their outer ends to seal the ends of the trunnions, and may be held in position by any suitable means.

Referring to Figs. 2 to 5, the pawl carrier 8 is provided with a handle receiving socket I2 at one end and is forked at the Opposite end to provide a pair :of ears I3 from the outer face of which extend the trunnions 9. It will be noted that the carrier 8 is longitudinally divided into two sections or` halves I4 and I5 respectively, one ofV the ears I3 extending from each of the respective halves; If desired, the member 8 may be divided .otherwise than longitudinally with one of the ears I3 on each section.` Extending inwardly from thefsinner faces of the respective ears I3 is a pairof cylindrically shaped pawl supporting members lli,Y the members I6 being axially aligned withp respect to vone another to form in eiiect la single cylindrical pawl support.l

Referring again to Fig. l, the movable pawl I'l is pivotally supported by the members I6, the pawl I 'lv being of slightly less thickness than the distance between the ears I3, and having a bore therein of approximately a slightly larger diameter than that of the members I6, whereby the two halves I 4 and I5 of the member 8 may be assembled with the members I6 positioned within the bore of the pawl I1, after which the two sec- Y tions may be permanently secured together by any suitable means, as for example, the rivet I8, and the rivets I9 passing through the lugs 2l formed on the respective halves. It will be noted that theaxis of the members I6 is offset from the axis of the trunnions 9, so that considerable leverage may be applied to the pawl I'I by means of a suitable handle inserted in the socket I2..

The pawl I'I is provided with teeth 22 at its upper end engageable with the teeth 'I on the rack member 2 so that as the socket portion of the member 8 is rotated downwardly about the axis ofthe'trunnions 9, the pawl I 'I will be moved upwardly, thus carrying the rack member 2 with it, the detent pawl, as previously mentioned, preventing the rack from moving downwardly after pressure is released on the member 8. The pawls 4 and I'I may be urged .into engagement with the teeth 'I on the rack 2 by any suitable means, as for example, a spring 23 having an upper portion 24s engageable with the pawl 4 and a lower por-- and the pawl to obtain sufficient lifting power, the axis of the pin must necessarily be positioned quite close to the axis 'of the trunnions, this distance normally being less than the sum yof the radius of the trunnions and the radius of the pin. As a result thereof it has been necessary to cut away a portion of the trunnion to permit the insertion of the pin between the ears, thereby weakening the structure and placing a denite minimum upon the distance between the axes. In the present construction the two sections is and I 5 are each constructed with their respective member l@ and trunnion S as an integral part of the respective section, this being accomplished, for example, by casting or forging and as nonoles are required in the carrier adjacent the trunnions 9, the members l5 may be positioned withV axes as close to the axis yof the trunnions .as de.- sired to obtain any desired amount of leverage.

A s illustrated in Figs. 3 and 5, the portions of sections 14 and t5, adjacent the handle receiving socket AI2, are provided with 'interlocking flanges 2t and 12] respectively 'along their meeting edges so that stresses `in the two sections lresulting from the application of'pressure to the handle in the socket I2 will tend to be distributed between the two sections I4 and l5. Obviously, if desired, the socket l2 may be circular or oval instead of rectangular as illustrated in the drawings, depending upon the type of 'handle to be used therewith. Likewise the member 8 may be provided with a suitable opening 2B adjacentthe inner end of the socket `I2 to provide means for preventing dirt and other -matter from acctmiulating inthe socket.

V In some cases it may be desirable to Aprovide a reinforcing 4pin 29 connecting the members I5, the pin merely being inserted in suitable recesses formed Vin the ends ofthe members IE so that stresses will `tend to be applied equally to both of ythe members i6. The pin 29 may be formed separately las illustrated or formed as an integral part of one of the members I6; likewise the member 8 may 4be provided with a stop 3l, engageable with the housing I to limitthe downward movement of the member 8.

,It will be apparent from the above description that I have provided a pawl carrier for use on jacks 'oft-he type described in which the pivotal axis of the pawl may be positioned as close as desired to the 'axis of the trunnions without any sacrificing of strength or efficiency of the device. Likewise it will be apparent that by suitably proportioning the dimensions of the mem-ber 8 it maybe readily used as a replacement for other prior types of pawl carriers without any changes in the remaining elements o f s uch jacks andobviously as there are no apertures or the like in my improved carrier, maximum strength and ef.- eiency 4is achieved.

Having thusdescribed my invention, it is obvious that various immaterial modifications may be made in the same without departing from the spirit of miv-invention; hence, I do not wish to be understood as limiting myself to the exact form, construction, arrangement and combination o f parts herein shown and described orkuses mentioned.

What I claim as new and desire to secure by Letters Patent is:

1. In a pawl carrier of the type described, the combination of an -elongated member divided into two separable sections, one end of said member being provided with handle engaging means thereon, the opposite end of said member being forked to provide two spaced opposed ears, one ear being carried by each section of said member, axially aligned trunnions extending outwardly from the respective ears, a pair of axially aligned abutting pawl supporting members inwardly extending from the opposed faces of the respective ,ears and integrally formed with the latter, the axis of said pawl VSupporting Vmembers being spaced from the axis of said trunnions, and means for securing said sections together.

2, In a pawl carrier of the type described, the combination of an elongated member longitudinally .divided into two separable halves, one end of said member being hollow to form a handle receiving socket, the adjoining edges of said halves adjacent said socket having interlocking hanges thereon, the opposite end of said member being forked to provide twospaced parallel ears, one ear being carried by each half of said member, axially aligned cylindrically shaped trunnions extending outwardly 'from the respective ears and integrally formed therewith, a pair yof axially aligned cylindrically shapedpawl supporting members inwardly extending from the opposed faces of the respective ears and integrally formed with the latter, said supporting members adapted 'to be Ypositioned in abutting relation within a 'bore extending through a movable pawl vfor pivotally supporting the pawl thereon, the ,axis ofsaid pawl supporting members being spaced from the axis of said trunnions a distance less than the sum of the radii of the cylindrical trunnions and respective pawl supporting members, and means for securing said halves together.

3. In a pawl carrier of the type described, the combination of an elongated l,member longitudinally divided into two separable halves, one end of said member being hollow to form a handle receiving socket, the adjoining edges of said halves adjacent saidY socket having interlocking anges thereon, theopposite end of said member being forked to provide two spaced parallel ears, one ear being carried by each half of said member, axially aligned trunnions extending outwardly from the respective ears `and integrally formed therewith, a pair of axially laligned pawl supporting members inwardly extending from the opposed faces of the respective ears and integrally formed ,with the latter, the axis of said pawl supporting members being parallel to and spaced from the axis of said trunnions, both of said axes being spaced from the longitudinal axis of said socket, reinforcing means connecting said supporting members., and means for securing said halves together including a plurality o f lugs on one of said vhalves cooperable with similar lugs on the other of said halves, fastening means connecting each pair of cooperable lugs. and additional fastening means passing through Said halves adjacent the inner end 0f said socket.

CHARLES A. CRANE.

REFERENCES CITED The following references are o f record in the file of this patent:

UNITED STATES PATENTS Number Name Date 555,255 Robinson Feb. 25, 1896 1,465,704 Wood Aug. 21, 1923 

